Dumfries and Galloway or the Trossachs?

yeah im a pathetic traveller on roads. I get very motion sickness and have a few times had to get out of the car or bus. the roads are very curvaceous....especially along Loch Lomond...especially after a night out drinking before heading to Glencoe in a bus from Glasgow...or maybe thats just the "air-borne stomach virus" I get every morning after.